8 C.F.R. § 258.1 – Limitations—General.

(a) Longshore work defined. Longshore work means any activity relating to the loading and unloading of cargo, the operation of cargo-related equipment [whether or not integral to the vessel], and the handling of mooring lines on the dock when the vessel is made fast or let go, in the United States or the coastal waters thereof.
1. (1) Longshore work is not included in the term “normal operation and service on board a vessel” for the purposes of section 101(a)(15)(D)(i) of the Act except as provided in sections 258 (c) or (d) of the Act.
2. (2) A vessel that uses nonimmigrant crewmen to perform longshore work, other than the activities allowed in particular circumstances under § 258.2 (a)(2), (b), or (c) of this part, shall be subject to a fine under section 251(d) of the Act.
(b) Port defined. For purposes of this section, the term port means a geographic area, either on a seacoast, lake, river, or other navigable body of water, which contains one or more publicly or privately owned terminals, piers, docks, or maritime facilities, which is commonly regarded as a port by other government maritime related agencies, such as the Maritime Administration.